Today the majority of the peoples of the planet live in nation-states, based upon the idea, if never the reality, of a single people, a single culture, a single rule of law and a single source of sovereign authority.  But will they continue to do so in the future?  None of the major challenges that confront humanity today – from climate change to disease, from terrorism to mass migration – can be handled effectively by single nation-states, no matter how powerful. The world is no longer made up only of states but also of an ever-increasing multitude of inter-state networks and organizations which recognise no borders.  Today we are beginning to see the emergence of a new, unprecedented, cosmopolitan order conceived in such terms as “transnational justice”, “trans-national governance”, “multi-level sovereignty”. Today, we are beginning to be able to imagine the very real possibility of a new global civil society. But what political form should this take? This book, by examining the history of the evolution of human society from the world’s first empires to today’s world of inter-state networks, argues that there exists the possibility of the emergence of new political forms of global federation that will bring the species closer to the possibility of a more harmonious, equitable and secure future.